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OEM Furnace Limit Switch 3 Inch Insert C340056P04 for Trane JM Parts:
$30.00
OEM Furnace Limit Switch 3 Inch Insert C340056P04 for Trane. normally closed safety device. If your furnace functions within safe limits, the switch remains closed, letting the control voltage pass right through it to keep the heating cycle running. If the plenum temperature spikes to 190°F, the internal bimetal disc snaps open, cutting the voltage to the gas valve to safely shut down the burners. It automatically resets (closes again) once the temperature drops back down to 160°F.
